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Battery disconnect for nominal 48v systems?

I appreciate the video and link but 480 volts DC is not 60 volts DC. From what I am learning if there are inductive components that detect AC currents and excess -- the will not necessarily detect anything DC at any similar magnitude. So I have to trash these AC breakers. They are good for nothing more than disconnects, maybe. Certainly no protection.
 
AC breakers will certainly trip on DC. The problem is they can't successfully interrupt the arc at as high a voltage, or as high an over-current.
Switches also. I've seen switches rated hundreds of volts AC at tens of amps, but only tens of volts DC and a couple amps.

Those breakers would hold off DC to their rated AC voltage, but couldn't disconnect under load.
They are only good for use on AC circuits.

Some models of Square-D QO breakers are rated for moderate DC voltage and moderate short-circuit currents.
 
I FOUND IT I FOUND IT I FOUND IT!!!

I've been looking for hours for a disconnect switch for my 48V system, Schneider, Mouser, AB, Digikey, McMaster-Carr, youtube and forums.... same issues as everyone here, my 48V system will operate a bit above 48V and really would like to respect mfg ratings if they say 'max 48V' then I don't want it.

In frustration I wanted to see how Victron was selling their 48V gear without an offering, go check their site and yeah they have the same looking switch as bunch of others (https://www.victronenergy.com/dc-distribution-systems/battery-switch-on-off) BUT they say it is "suitable for battery systems up to 48V"!? Now they have a reputation to protect and IANAL but sounds suspiciously enough to win a court case if my 48V system which runs up to 52V goes up in flames (hyperbole I know but you get my point) soooooo maybe?

Since I really don't want to design around legalese I go check their datasheet:
and
"Maximum DC operating voltage 60V"
W00T!

It even says "The battery switch is suitable to switch under load", so I am saving copy of the datasheet and bought 2, thought others might like to know :cool:
 
... BUT they say it is "suitable for battery systems up to 48V"!? Now they have a reputation to protect and IANAL but sounds suspiciously enough to win a court case if my 48V system which runs up to 52V goes up in flames (hyperbole I know but you get my point) soooooo maybe?

Since I really don't want to design around legalese I go check their datasheet:
and
"Maximum DC operating voltage 60V"
W00T!

It even says "The battery switch is suitable to switch under load", so I am saving copy of the datasheet and bought 2, thought others might like to know :cool:
Great find.

It pays to look at the data sheets 👍

I'm surprised that hadn't been pointed out yet.
 
Of course it works, don't see anything about UL.
Probably just a matter of standards.
But I was surprised they said it could be switched under load.
 
These small rotary switches can be used, but great caution should be taken when disconnecting. There should be no load on it at all to avoid contact damage. With contacts in such close proximity and moving apart with the speed of only a hand movement instead of a rapid triggered motion, it would could expose the contacts to a prolonged damaging arc. Comparably, consider DC stick welding commonly reaches 50 volts in the 100/200 amp range. What is surprising is how long you can draw the arc away before it is extinguished. The for mentioned reason is why I much prefer using a high voltage DC breaker, not so much for its current interrupt, but for its disconnect ability. For current interrupt, I prefer a T class fast blow fuse.
IMG_1277.jpeg
 
These small rotary switches can be used, but great caution should be taken when disconnecting. There should be no load on it at all to avoid contact damage. With contacts in such close proximity and moving apart with the speed of only a hand movement instead of a rapid triggered motion, it would could expose the contacts to a prolonged damaging arc. Comparably, consider DC stick welding commonly reaches 50 volts in the 100/200 amp range. What is surprising is how long you can draw the arc away before it is extinguished. The for mentioned reason is why I much prefer using a high voltage DC breaker, not so much for its current interrupt, but for its disconnect ability. For current interrupt, I prefer a T class fast blow fuse.
View attachment 195378
I've been looking for DC CB's, do you have experience with this brand? Are they well made and reliable?
 
I used this Watts24/7 breaker and put it in a box. The breaker looks to be a rebranded DIHOOL. I’ve opened it and it appears to be well built and designed for the job. Hasn’t failed, but it’s not like it’s gone through any test. I’ve always reduced load before opening contracts, though I wouldn’t hesitate if needed.
IMG_0777.jpeg
 
That being said, I don’t believe that the contacts move any faster than manually turned.
 
I FOUND IT I FOUND IT I FOUND IT!!!

I've been looking for hours for a disconnect switch for my 48V system, Schneider, Mouser, AB, Digikey, McMaster-Carr, youtube and forums.... same issues as everyone here, my 48V system will operate a bit above 48V and really would like to respect mfg ratings if they say 'max 48V' then I don't want it.

In frustration I wanted to see how Victron was selling their 48V gear without an offering, go check their site and yeah they have the same looking switch as bunch of others (https://www.victronenergy.com/dc-distribution-systems/battery-switch-on-off) BUT they say it is "suitable for battery systems up to 48V"!? Now they have a reputation to protect and IANAL but sounds suspiciously enough to win a court case if my 48V system which runs up to 52V goes up in flames (hyperbole I know but you get my point) soooooo maybe?

Since I really don't want to design around legalese I go check their datasheet:
and
"Maximum DC operating voltage 60V"
W00T!

It even says "The battery switch is suitable to switch under load", so I am saving copy of the datasheet and bought 2, thought others might like to know :cool:
Great find of the updated data sheet and manual.

Though it does say this, prob not ideal to use as a regular disconnect when under load but for emergency use or when you have control of loads should be ok:

Screenshot_20240219_094057_Samsung Notes.jpg
 
i was trying to find an answer to this riddle as well. The one I came across in the forums was another marinco bep product.

Up to 120vDC and 400 amp continuous.

I’m not sure what amperage you will need. I also looked into breakers but found that more confusing with all the single pole versus double and whether they should be used as a disconnects or not.

Great find on the Victron data! I had checked them out not long ago and had thought they were like the rest off the 48v max crowd.
 
i was trying to find an answer to this riddle as well. The one I came across in the forums was another marinco bep product.

Up to 120vDC and 400 amp continuous.

I’m not sure what amperage you will need. I also looked into breakers but found that more confusing with all the single pole versus double and whether they should be used as a disconnects or not.

Great find on the Victron data! I had checked them out not long ago and had thought they were like the rest off the 48v max crowd.
May want to check the reviews on that one.
 
May want to check the reviews on that one.
More stuff to add to the confusion eh? One guy calling it the holy grail the next saying it blows up in smoke.

That right there is the reason I’m here on the forums trying to seperate trash from treasure in the solar world 😝

I came across it in this thread here and was UL listed by a reputable company so thought it was one peeps on here used.

I will say the victron states it can switch under load and the bep states clearly not to do that on its model.
 
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"Tested to UL1107 ignition protection" implies not UL Listed.

I had to wonder about Victron switch under load. These aren't spring loaded switching, are they?
How good are you holding an arc with a buzz box welder?
 
I personally went with a Noark 250A UL489 listed MCCB breaker. Since I had expanded my system the 250A was not enough and thought I was going to have to get something else.. but realized you can get a mechanical interlock for them so I got a 2nd 250A breaker. Once I install that I will safely be able to run 400A continuous, have reliable over current protection for entire battery bank, and have a reliable disconnect even while under full load.
 
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